After a couple of days of work I finally got zimbra running in a openvz box, everything worked fine for a day or so with kmail and thunderbird to send emails (smtp tls if available), but today I tried to get outlook client running with zimbra and modified the configuration.
Following this wiki entryhttp://wiki.zimbra.com/index.php?tit..._Configuration
I enabled these two lines in master.cf
#smtps inet n - n - - smtpd
# -o smtpd_tls_wrappermode=yes -o smtpd_sasl_auth_enable=yes

now, nothing is working anymore, even not when I switch it back and check with thunderbird or kmail.